About Arisaema serratum (Thunb.) Schott
Arisaema serratum (Thunb.) Schott is a species of flowering plant in the arum family, Araceae. It is a perennial plant native to Japan, found from the Kansai region north to the island of Hokkaido, and grows naturally in damp forests. It produces two leaves, each with 7 to 20 leaflets, each bearing 7 to 13 leaflets. The color of its flowering bract is variable, appearing either purple or green. It blooms between May and June. Arisaema serratum is closely similar to Arisaema mayebarae, which is restricted to Kyushu — an island where Arisaema serratum does not occur. Arisaema serratum can be told apart by its shorter spathe blade, which droops over the tip of the opening, rather than being held at a horizontal angle like that of Arisaema mayebarae. All parts of Arisaema serratum contain needle-like calcium oxalate crystals, saponins, and coniine. Toxicity is most concentrated in the underground bulb. Touching the plant’s juice triggers skin inflammation. If ingested, it causes intense pain from the mouth through the throat, to the point that swallowing becomes impossible. Poisoning symptoms include diarrhea, vomiting, and respiratory paralysis, and severe cases can be fatal.
